What we did
- Excavated trenches to public-private boundary;
- Laid pipework and ducting;
- Gas pipes connected.
This week was pretty hectic, with lots of busy spades, angry neighbours and bundles of cables (as well as bundles of nerves) as we did much of the work to connect the houses to the water, gas, electric and telephone utilities.
Quite a long one here, with a lot of important tips, details and learnings. But first, me on video.
I was always advised that coordinating the utility installations would be one of the trickiest times; utility providers work to their own schedules, there are always surprises when excavating, and on top of that, there are lots of regulations to adhere to.
That said, we set out a plan to dig a single trench carrying all the pipework and cables to the boundary by the main road. Vitally, I planned for this to avoid the main access way to limit any disruption – you can see the planned route in the pic below, which also shows the gas service connection points.
At the boundary, specialist utility connection contractors with WIRs, GIRs and NERs qualifications would connect our pipework and cables to the main services.
Below I briefly explain who can do what and what the process is.
A qualified company with GIRS accreditation lays the yellow MDPE pipe straight into the ground, including on private land, and connects it to the mains in the public domain. Given this, the whole trench from the property to the boundary must be excavated and left open until the date of this connection. Other utility connections did not require this, so excavation may be planned around this connection date in order to minimise disruption.
The yellow gas pipes terminate at a gas meter supplied by the future chosen gas supplier and is usually connected up outside. For us this meant we have to deal with an ugly gas meter box outside the main door =-/
This connection was completed during this week.
First, the developer lays a blue MDPE service pipe on private land from inside each property to the boundary. The pipe-run is then inspected by the connections company, in our case Thames Water, prior to being connected to the mains, with a meter and ‘stopcock’ valve installed at the boundary. Only the main regional water distributors tend to do this given the heavy regulation imposed on those with the necessary WIRs accreditation to be able to form connections to mains. This is due to the risk of contamination to the public water supply. An inspection, including test-run are then done after this.
For us, this connection will be made in a couple of weeks.
This is all in contrast to the foul (sewage) connections which can be done by someone who is deemed ‘competent’, after making an application to the main water company.
Like with gas pipes, electrical cables on public and private land are laid by a qualified company, with the NERs accreditation. However, these are run through black plastic ducting, so can be simply pulled through using a string which has already been laid by the developer. The qualified electrical contractor will then connect this cable to the main public power supply, with the other end in the house connected to a meter supplied by the future chosen electricity supplier and then on to the main fuse box/consumer unit.
This will be done in a few weeks after we get the necessary approvals.
Telephone lines are similar to electrical cables and even carry a small current, which explains why the phones still work when the electricity goes out. I didn’t research qualified contractors so heavily after I found out BT will provide equipment and connect the service for free(!), but I believe other companies can provide connections.
This will be done after the electrical second-fix, when all the electrical and phone sockets have been installed.
Burying all the cables safely
With all these cables buried within the same trench, strict guidelines have to be adhered to, ensuring a minimum distance between certain cables as shown in the below diagram from the gas installation guidelines. Coloured tape is also laid on top of the corresponding pipe/cable so anyone excavating there in the future is aware what’s beneath.
I actually found much of this process opaque, with few accurate and reliable resources online to help you, requiring a lot of questions to generous people. Here are a couple of resources by Built It and The Self Build Guide which I used for reference.
Work this week
As well as telling me how tough this process would be, others also told me it would be impossible to coordinate this perfectly. Despite that (unsupportive) advice, we had to try our best to cause the least disruption as possible to the shops and existing tenants, meaning keeping the window of excavating, laying cables/pipes and then backfilling as tight as possible, and preferably out of normal working hours. The key date here was the gas connection, which as above, had to be done with the trench open. With that, I scheduled it for Saturday, so we could reinstate the trench over the weekend.
On with the digging
With the hard deadline set, excavation began mid-week, first with the digger, its legendary operator and his pack of Marlboro. However, where we were met with existing pipes and cables in the ground, extra hands were called in to pick away by hand, who happened to be the digger’s young nephews! Many of the existing cables were identified using both utility survey maps and a mobile CAT scanner. Both of these are notoriously unreliable, so to be safe, the team dug a lot of the trench by hand to avoid hitting anything.
After a lot of prayers, we managed to narrowly avoid any issues, and with minutes to spare, have the open trench ready for the gas contractor.
The next turn I couldn’t have planned for… hungover contractors. To be fair, they had to wait a short while for us to rectify some issues, but were close to calling off the job that day. This is when McDonald’s genuinely came to the rescue, keeping them onsite and nursing them enough to complete the gas connection!
After this, the team put in a solid shift late into Saturday to reinstate the road and customer parking, ready for the shops next week.
During the following week, we remained in the mud, working on reinstating the rest of the trench back to the houses. Also check out part 2 of this guide in week 27, where I continue to explain how the pipework and cables are run into the new properties.